Sci-fi is hard to translate to music, as is fantasy. Lots of attempts to write Moorcock songs, Veteran of the Psychic Wars and Black Blade by Blue Oyster Cult, notably. Maybe one of the best was an ancient one by Crosby, Stills and Nash, Wooden Ships. It could be argued Donovan's fantasy Atlantis is in the same group. Most songs are about getting famous, getting laid, and getting left.